text: Despite their apparent simplicity, retinalophototrophs boast versatile ion usage that translates to their existence in relatively extreme environments. For instance, retinalophototrophs can thrive at depths over 200 meters where, despite a lack of inorganic carbon, sufficient light as well as sodium, hydrogen, or chloride concentrations harbor conditions capable of supporting their vital metabolic processes. Studies have also shown sodium and hydrogen ions correlate directly with retinalophototroph’s nutrient uptake and ATP synthesis, while chloride drives processes responsible for osmotic equilibrium. Even though retinalophototrophs are widespread, research has shown they can be niche too. Depending on their proximity to the oceans surface, retinalophototrophs have evolved to be better at absorbing light within specific wavelengths. Most importantly, retinalophototrophs prevalence as a primary producer contributes substantially to the bottom-up mechanics of marine environments and, consequently, success of fauna and flora worldwide.
  Although retinalophototrophs are less efficient at converting light than chlorophototrophs, the simplicity makes it the preferred system in a large number of environments. For example, because retinalophototrophs requires no iron in the reaction center, they are well-adapted to the iron-poor ocean environment. At high light level, they are more efficient in terms of protein investment to energy output due to the small size.